An infusion pump is a medical device commonly used to infuse fluids or medicaments to a patient.
In particular, an infusion syringe pump is a device which drives a syringe plunger of a syringe at a predetermined rate, thereby expelling fluid from the syringe and then on through a tube to the patient. Typically, syringe pumps comprise a motor that drives a screw or gear mechanism to move a pushing surface (drive head) at a controllable rate. The rate of movement of the pushing surface or drive head can be predetermined by a medical practitioner such as a nurse in order to infuse fluid from the syringe at the desired rate of administration. The rate of flow can be precisely controlled and extremely low rates of infusion can be achieved, for example 0.1 ml per hour infusions, which could not be achieved using gravity infusion (i.e. a so-called “drip”).
A syringe pump typically comprises a body or housing which is adapted to receive the non-moving body of a syringe, i.e. the syringe barrel. This portion of the housing is known as the syringe cradle. There may be a groove in the syringe cradle in which a flange of the syringe barrel can be located in order to immobilise the syringe barrel from longitudinal movement during longitudinal movement of the syringe plunger within the barrel.
The syringe plunger has a plunger flange which is connected to the syringe piston by a syringe plunger stem. When mounting a syringe in the syringe pump, the plunger flange is held beside the syringe plunger drive head which may additionally be provided with a retaining arm or arms for holding the syringe plunger at a correct centred position. A syringe barrel clamp or clip may also be provided to clamp the barrel in a predetermined position.
As known in the art, the drive head is connected to a screw drive mechanism for connecting the linear motion of the screw drive mechanism to the syringe plunger in order to empty the syringe.
The prior art syringe pump is typically provided with a control panel or buttons for the user to program the desired infusion. The user can typically input the drug to be infused, the syringe brand and size and the desired infusion rate or duration of infusion. The device is also provided with a display which firstly allows an operator to view his or her inputs from the control panel as he or she programs the pump, and also provides information to the operator whilst infusion is in progress. Such information could include, for example, “infusion time remaining” (i.e. time remaining until all fluid is expelled from the syringe) or “infusion volume remaining” (i.e. VTBI=“volume to be infused”).
Typically, manufacturers have attempted to keep syringe pumps as small as possible for ease of mounting on a mounting frame, easy handling and in order to save space around a patient's bedside. One way to achieve this in the past has been to provide displays which have a large width but low height i.e. relatively long but thin displays. Whilst these custom displays can be considerably more costly than displays of standard size which are commercially available from suppliers “off the shelf”, the displays of standard size may be of unsuitable proportion for a compact syringe pump.
In addition, a practitioner typically wants to see both the electronic display but also the syringe barrel itself to provide an immediate visual representation as to the state of the infusion.
It is therefore an object of the present invention to provide a syringe pump having a display of cost-effective size whilst also providing space for the syringe barrel itself to be viewed.